This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. The National Institute of Standards and Technology has tasked NMRFAM with characterizing and quantifying the most abundant metobolites in human serum. This will be accomplished using 1H-13C HSQC and 1H-1H TOCSY.